Tool and retaining means therefor



' JanYZO, 1931. 1 vEfw. STEVENS ,7

' TOOL AND RETAINING MEANS THEREFOR Filed Jan. 1'7, 1928' BI CZYCI 7 gayINVENTOR. [Fa Ward W Sfevens VQM Z. W

A TTORNE Y.

Patented Jan. 20, 1931 UNITED STATES PATENT OFFICE EDWARD w. STEVENS, orDETROIT,

TooL comm, or NEW YORK,

MICHIGAN, AS SIGNOR TO CHICAGO PNEUMATIC N. Y., A CORPORATION 01 NEWJERSEY TOOL AND RETAINING mmns Tnnam'oa Application flled January 17,1928. Serial No. 247,814.

used for cutting, punching, rivet busting and the like. In some respectsit may be considered as a further development of and improvement uponthe structures disclosed and 1 claimed in my Patent No. 1,609,136 issuedNovember 30, 1926, for retainerfor rivet:cutting tools.

In using a tapered tool with Ia retainer of the type disclosed in theabove patent, the '15 tool frequently wedges in the opening in thebarrel nut retainer thereby causing annoyance and delay to the operatorwho is under the necessity of freeing the tool by striking the sameagainst the work or by loosening it by blows with another tool.

One ob ect of the invention is to provide an improved arrangementbinding and wedging of the tool. Other objects will be apparent from thedetailed description which follows.

In order to illustrate the invention one concrete embodiment thereof isshown in the accompanying drawings in which:

Fig. 1 is a sectional view through the front end of a percussive machinedisclosing a tool of the described type with retaining means therefor;

Fig. 2 is a front end elevational view of a detail of the retainerarrangement;

Fig. 3 is a front end elevational view of the tool shown in Fig. 1;

Fig. 4 is a top plan view of the working tool similar to that shown inFigs. 1 and 3 butwhaving a chisel end.

.The embodiment of the invention chosen for the purpose of illustrationcomprises a working tool A or A arranged to be secured to the front endB ofa percussive machine 0 any suitable or desired type by retainingmeans'indicated at C. As indicated, the tool A projects within the frontend of the percussive machine, such as the cylinder B of a pneumatichammer to receive upon its shank end the blows of the percussive membersuch form of tapered tool and retainer therefor which will prevent fpreference the outer end of retainer as piston B. The retaining means Cconforms substantially to that disclosed in my Patent No. 1,609,136,referred to above, having latching blocks 0 carried by an annular spring0' and engaging suitable recesses in cylinder B .of the percussivemachine. annular locking nut 0 such as disclosed in my copendingapplication Serial No. 94,684- filed March 15, 1926, may be utilized tolock the barrel retainer C against removal.

As indicated in Figs. 1, 3 and 4, working tool A, which may take theform of a punch as shown in Fig. 1, or A in the form of a chisel asindicated in Fig. 4, or have a working end of any other desired shape,has a tapered portion (1 extending towards the working end, said endprojecting through a bore in retainer 0 which is in axial alignmentwith'the piston chamber of the percussive machine. Suitable means areprovided for guiding working tool A or A for limited movement relativeto machine B and retainer 0 without wedging or binding while positivelypreventing its ejection from retainer C. The preferred means is a splineand groove construction. For convenience in' manufacture the splines areon the retaining means while the grooves are formed in the workingtool.. By preference two splines 5 (Figsl and 2) are provided atdiametrically opposite points and projecting into the bore provided bythe tool retaining means and through which the working tool extends. Theworking tool has cooperating grooves 6, Figs. 1, 3 and. 4, atdiametrically opposite points in the tapered portion a thereof, thesegrooves being in substantial parallelism with the axis of the tool asindicated in Fig. 1. The ends 7 of grooves 6 cooperate with splines 5 toform stops limiting the outward movement of tool A relative to retainerC.

While the splines may be formed upon barrel nut retainer C directly ifdesired by is formed with an inturned flange c (Fig. 1) leaving anopening of substantial size and a separate abutment piece or collar 8 isprovided having a bore of reduced size with the splines 5 extendingtherewithin. Abutment collar 8 has a radially projecting flange 8a 100which cooperates with flange c of retainer r and an extended portion 86which telescopes within the bore of flange a. By preference also, anadapter bushing 9 is provided which fits within the end of cylinder B ofthe percussive machine and receives the shank end of the workin toolwhich may be tapered if desired as in icated at a the inner surfaceenough to wedge or bind in the bore. the present invention permits theuse of a of the bushing being shaped to fit the shank of the tool. Aspacing collar 10 of resilient material such as' rubber is disposed inretainer 0 yieldingly to maintain bushing 9 and abutment 8 in engagementwith cylinder B and flange a, respectively, the inner diameter of collar10 being 'suflicient to permit free movement of the working tool Awithin the limits provided by the bushing 9 and by the cooperating stops5 and 7 When tool A is at the outer limit of its movement,

' the force of theblow delivered by piston b tool of greater strengthand endurance b reason of its tapered shape without the di ficultiesheretofore experienced in using such tools which result from theirtendency to wedge and bind in retainers of the barrel type and withoutthe disadvantages due toloose fit of the tool in the retainer when it isin its rearward position.

While a preferred form of the invention.

has been herein shown and described, it is to be understood that theinvention is not restricted to the specific details thereof but coversall changes, modifications, and adaptations within the scope of theappended claims.

I claim as my invention '1. The combination witha percussive machine ofa working tool extending into said machine to receive the blows thereof,said tool being tapered toward its working end,

and retaining means for said tool providing a spline and grooveconnection permitting limited movement of the tool'without binding orwedging of the tapered portion thereof with the retaining means on saidmachine, said tool and means requiring mounting of the former in thelatter as a prerequisite to the insertion of the tool in and theapplication of said means to said machine.

2. The combination with a percussive mawithin said retainer, said collarchine of a working tool extending into said.

passage therethrough of said tool, an abutment collar within saidretainer for preventing the ejection of said tool, and cooperating guidemeans on said abutment member and on the tapered portion of said toolpermitting limited movement of the latter but preventing wedging engaement of the tapered portion of said tool w1th said collar and insertionof said tool in any other manner except from the interiorof saidretainer.

4. The combination with a percussive machine of a working tool extendinginto said machine tov receive the blows thereof, said tool being taperedtoward its working end, a barrel retainer secured to said machine andhaving an inturned flange at its outer end providing an opening of asize to permit pas-' sage therethrough of said tool, a flanged the endflange of said retainer for preventing the ejection of said tool, andcooperating guide means on said abutment member and on the taperedportion of said tool permitting limited movement of the latter and itsinsertion only before said retainer is applied to. said machine butpreventing wedging engagement of the tapered portion of said tool withsaid collar.

5. The combination with a percussive machine of a working tool extendinginto said machine to receive the blows thereof, said tool being taperedtoward its working end, a barrel retainer secured to said machine andhaving an inturned flange at its outer endproviding an opening of a sizeto permit passage therethrough of said tool, an abutment collar for.said tool slidabl fitting aving a radial flange for engagement with saidretainer flange and having an extended portion for telescopingengagement with said abutment flange,and cooperating guide means on saidabutment member and on the tapered portion of said tool permittinglimited movement of the latter and its insertion only'before saidretainer and member are applied to said machine but preventing wedgingengagement of said tool with said collar.

6. The combination with a percussive machine of a working tool extendinginto said abutment collar arranged to cooperate with machine toreceive'the blows thereof, said tool being tapered toward itsworkingend,

.collar and the tapered portion of said tool permitting insertion ofsaid tool only from within said collar and limited movement of the samewithout permitting wedging or binding of the tapered portion of saidtool in said collar.

7. The combination with the cylinder of a percussive machine of atapered working tool arranged to extend within said cylinder 'toreceiving the blows of said machine, an-

adapter bushing extending within said cylinder to receive the shank ofsaid tool, a barrel retainer secured to said cylinder, an abutmentcollar within said retainer, resilient means encircling said 'toolbetweensaid adapter and said collar to maintain the same yieldingly inspaced relation, and cooperat- 1ng means on said collar and on'thetapered portion of said tool providing a positive stop while ermittinlimited movement of said tool without w ging or binding.

8. The'combination with the cylinder of a percussive machine of atapered working tool'arranged to extend within said cylinder toreceiving the blows of said machine, an adapter bushing extending withinsaid cylinder to receive the shank of said tool, a barrel retainersecured to said cylinder, an abutment collar within said retainer,resilient means encircling said tool between said adapter and saidcollarto maintain the same yieldingly in spaced relation, and cooperatingmeans on said collar and on the tapered portion of said tool providing apositive sto while permittin limited movement of sai tool without w gingor binding, said means comprising a spline on said collar engaging agroove in said tool in substantial parallelism with the axis of thelatter.

9. The combination with the cylinder of a percussive machine of atapered working tool arranged to extend within said cylinder toreceiving the blows of said machine, an adapter bushing extending withinsaid cylinder to receive the shank of said tool, a barrel retainersecured to said cylinder, an abutment collar within said retainer,resilient means encircling said tool between said adapter and saidcollar to maintain the-same yieldingly in spaced relation, andcooperating means on said collar and on the tapered portion of said toolpermitting limited movement of said tool without wedging or bind ing,said means comprising diametrically opposed splines on said collarslidably received in grooves in said tool in substantial parallelismwith each other and with the axis of the tool, the ends of the groovesengaging said splinesas stops.

10. A working tool for use with a percussive machine, said tool havin a'portion tapered toward its working en and an axial groove having an openend and extending partially into said portion in substantial parallelismwith the axis of the tool.

11. A working tool for use with a percussive machine, said tool havingreversely tapered portions extending substantially to the ends thereofand diametrically opposed axial grooves with open ends and insubstantialparallelism with the axis of the tool extendmg partially intothe tapered portion which leads to the working end of the tool.

Signed b me at Detroit, in the county of Wa e, an State of Michigan,this 14th day of anuary, 1928. v

4 EDWARD W. STEVENS.-

